Cauda Equina Syndrome after Alcohol Sclerotherapy due to Misdiagnosed Talov Cyst : A case report.
BACKGROUND : Tarlov cyst (TC) as known as perineural cyst are usually found in the sacral region, asymptomatic and incidental findings. Endopelvic extension of TC is rare and can be misdiagnosed for adnexal mass.
CASE : We report a TC misdiagnosed to adnexal cyst in a 38-year-old woman. She was visited to local gynecology hospital for regular checkup. Pelvic ultrasonography finding was left 6cm ovarian cyst incidentally and treated by alcohol sclerotherapy (100% alcohol irrigation, 20cc). After that, she presented both lower leg weakness and left leg radiating pain. In manual muscle test, muscular weakness was observed in both lower limbs : hip flexor 3+/3 (right/left), knee extensor 3+/3, ankle dorsi flexor(ADF) 3+/3, hallucis extensor 3+/3, and ankle plantar-flexor(APF) 3+/3 grades. The patient had sensory change below L4 dermatome. The bulbocavernosus reflex (BCR) was absent. The anal tone was decreased. Patient had anal sphincter weakness and neurologic bladder symptom of incontinence, nocturia. Ankle clonus and Babinski sign were negative. Lumbar spine MRI finding was 6.5*5.0cm sized anechoic cyst in perineurium of sacrum extension to pelvic cavity with bony erosion. In motor and sensory nerve conduction study, both common peroneal, tibial, superficial peroneal and sural nerve conduction was normal. In needle electromyography (EMG) 3month after sclerotherapy, left tibialis anterior, gastrocnemius, vastus medialis, tensor fascia lata, gluteus maximus and S1 paraspinal muscle presented abnormal spontaneous activity (ASA), normal motor unit action potential (MUAP) and reduced single recruitment pattern. Left peroneus longus and biceps femoris presented ASA and polyphasic MUAP, reduced single recruitment pattern. Both external anal sphincter muscle presented ASA. Left external anal sphincter presented polyphasic MUAP, reduced complete recruitment pattern. In somatosensory evoked potential test (both tibial nerve), left side latency was more delayed and waveform was more attenuated than right side. In H-reflex, delayed latency was presented on left side. BCR latency test was no response. Those EMG findings were corresponding with cauda equina sydrome (CES). In isokinetic test, difference of right and left ADF peak torque was 78.0%. In balance test, overall balance index was 10.7°. Electric stimulation therapy, strengthening, gait exercise and stretching was done 3 times per week. After 6 months, weakness, radiating pain, incontinence, anal sphincter weakness and sensory change were improved. In follow-up EMG, CES was partially improved state. In follow-up Isokinetic test, difference of right and left ADF peak torque was 14.3% (Left side was better). In follow up balance test, overall balance index was 6.7°.
CONCLUSION : This is very rare report of recovery of iatrogenic chemical CES in patient with tarlov cyst |
